1. Field of the Invention
The present invention relates in general to a fuel measuring device, more particularly, to a fuel measuring device having a non-intrusive (or non-contact) structure between a rotor and a magneto resistive sensor, resulting in reducing of measurement errors that are usually caused by imperfect mechanical contact or corroded contacts.
2. Description of the Related Art
In general, a fuel tank out of a fuel supply system is a device for storing fuel, and has a built-in fuel gauge for use in displaying fuel measurements to a dash panel of an automobile.
The fuel gauge for use in the fuel tank includes an adjustable resistive type sender unit 10, a coil-type receiver unit 20 connected to the adjustable resistive type sender unit 10, and a battery 30.
The adjustable resistive type sender unit 10, as shown in FIG. 1, includes a float 12 disposed inside the fuel tank 11, moving in the vertical direction with the liquid level of the fuel, a rotary rod 13 connected to the float 12 and rotatably disposed in the upper portion of the fuel tank 11, a contact arm 14 interlocked with the rotary rod 13 and installed outside of the fuel tank 11, and a variable resistor 15 having a variable resistance according to its contact with the contact arm 14 (please refer to Korean Patent Laid-Open No. 2003-0006361).
However, the above-described adjustable resistive type sender unit 10 is influenced by contact resistance. Unfortunately therefore, measurement errors and the frequency of error occurrence caused by deterioration of durability and non-uniformity of the variable resistor 15 are high.